Minprovise is focused on how optimisation can help to reduce energy consumption while improving yield quality and quantity.
Mining, and crushing in particular, is as old as farming or sailing. It’s used to liberate diamonds, extract gold, supply iron ore and produce the concrete from which our cities are built.
Mining consumes a significant portion of the world’s energy, and the responsible path ahead must involve optimisation of mining activities. That includes reducing the energy consumed while maintaining production, as well as improving yield quality and quantity.
Optimisation within the crushing arena is still a relatively unexplored area. As a company serious about innovative solutions, Minprovise is focused on how crusher circuit efficiency can improve yield through optimisation.
“The art of crushing rocks will always consume energy, but how that energy is applied can improve yield through efficiency,” Minprovise general manager of engineering John Minnaar said.
Minnaar explains that in most precious metal and base metal applications, wet processing is applied after crushing, with a focus on stabilising and optimising the process. A stable and steady process flow ensures efficient application of chemicals and maximum extraction of the product.
The upstream crushing circuit is usually oversized with a buffer stockpile separating the circuits. This is due to the surging nature of the crushing process.
“Crushers are not often optimised or given much attention beyond maintenance if they keep up with feed demand,” Minnaar said. “Many circuits are inefficient and power-hungry. We are aiming to change this.
“In the case of iron ore and aggregate, the crushing process requires a stable flow to produce the final product. In the modern mining era, it’s easier to design a larger crushing plant with sufficient capacity to compensate for losses due to surges and breakdowns, but we have an innovative solution to optimise even these power-hungry plants.
“Operating a crushing plant can be compared to driving a 4×4 vehicle.
“When driving in rough terrain, the vehicle is subjected to high, and sometimes low, power demands. The shock loading on the vehicle can cause parts to fail prematurely, while the fuel consumption is extremely high.
“When the same vehicle is used to commute, using sealed city roads, fuel consumption is reduced and moving parts last a long time. It’s not as exciting as offroad, but the efficiency of smooth and stable use is much more cost effective.
“Crushing circuits are similar. When the feed tempo is consistent and the equipment balanced to the production demand, production cost is reduced and equipment lasts longer due to fewer impact loads.
“If the equipment is pushed to its limits without consideration to cyclic loading, the entire circuit is subjected to unnecessary impact, wear and tear, risking failure or require more frequently needed maintenance cycles.”
Another consideration often overlooked is a plant’s bottleneck. A healthy plant is operated to the maximum capacity of the bottleneck equipment (this determines the overall plant capacity) while configuring all other equipment to achieve this consistent maximum.
Minnaar feels understanding the principal of the bottleneck seems to be lost in modern mining, where quantity trumps quality. Minprovise advocates for better quality resulting in more long-term revenue and fewer shutdowns.
As an original equipment manufacturer (OEM) crusher agent and specialised crusher maintenance service provider, Minprovise see the best and the worst of operating philosophies. The most common mistakes made are not optimising crusher circuits.
Minnaar points to the company’s years of experience teaching operating teams to adjust their equipment set-up and process philosophies to achieve a more consistent production rate, reduce unwanted component failure and operate plants more efficiently. This overall optimisation of any circuit results in greater revenue for companies and shareholders.
Minnaar has found that many mines operate an ageing fleet of crushing equipment requiring high maintenance cost and unplanned downtime. The cost to frequently replace worn parts often exceeds the value of upgrading the equipment to the latest technology.
“At Minprovise, we have the knowledge, technology and control systems to assist clients in the optimisation of their crushing plants. The 80–20 rule applies here,” Minnaar said.
“Having the correct equipment selection and set-up takes you 80 per cent of the way; the last 20 per cent is optimisation achieved through on-line monitoring of the process and actively controlling characteristics of the circuit; for example, crusher gap control.
“These incremental improvements further increase revenue for our clients.
“While mining may well be an age-old pursuit, crusher circuit optimisation is modern and achievable. It’s an innovative solution that fine tunes the circuit to produce better quality yield with fewer shutdowns, less risk, less expense and less waste.
“It shifts the conversation from replacement component price comparison to sophisticated extraction of quality product.”
This feature appeared in the June issue of Australian Mining.